Daniel Malmer developed the initial API scaffolding for document reference counting within the GROQ evaluator in the sanity-io/groq-js repository. He introduced new functions to the documents module, enabling incoming reference counts to be queried with type-safe guarantees. Using TypeScript and JavaScript, Daniel focused on robust type system integration and test-driven development, providing placeholder implementations and comprehensive tests to ensure correct type and signature recognition. While the work did not address bug fixes, it established a foundation for improved reference tracking and future performance optimizations, demonstrating depth in backend and API development as well as careful attention to maintainable code structure.